Official vs Contrib

Official vs Contrib

The official OpenCV AAR (org.opencv:opencv:5.0.0.1) ships core modules only. The opencv_contrib modules require rebuilding the SDK from source — or using a prebuilt build that includes them.

In the official AAR (core)

core · imgproc · imgcodecs · videoio · video · calib · features · dnn · objdetect (QR + DNN detection) · photo · stitching

Contrib (NOT in the official AAR)

Module	Purpose
face	Face recognition (LBPH, FaceRecognizerSF)
tracking	CSRT, KCF, MOSSE trackers
aruco	ArUco / ChArUco markers (AR, calibration)
text	Scene text detection (EAST, DB, CRNN)
xfeatures2d	SURF, DAISY, BEBLID
ml	SVM, KNN, DTrees — moved from core in 5.0
xobjdetect	Haar cascades, HOG — moved from core in 5.0
gapi	Graph API — moved from core in 5.0
ximgproc, xphoto, bgsegm, optflow, img_hash, wechat_qrcode, …	25+ more

Full list: docs/official-vs-contrib.md.

Getting contrib

• Rebuild from source (opencv + opencv_contrib, CMake, NDK, build_sdk.py) — supported but slow and error-prone.
• OpenCV Pro — prebuilt AAR with core + all contrib for 5.0. One Gradle line, arm64-v8a + x86_64, no rebuild.